FRANKLIN TWP — Two children and a man were flown by medical helicopters to hospitals this morning following an accident on Route 422. State police at the scene said a NOGA Ambulance van was taking a 74-year-old man to VA Butler Healthcare when it was struck in the rear by a R. Williams Paving, a Pittsburgh-based paving company, van carrying the two boys. The accident occurred just after 9 a.m. The ambulance with NOGA Ambulance, which offers non-emergency transport service, was stopped in eastbound traffic that was backed up due to a construction zone up the road. The accident occurred right before the intersection with Route 528. The father of the two boys was the driver of the van. He was taken to Butler Memorial Hospital with injuries. The driver of the NOGA Ambulance and an aide were both taken to Jameson Hospital in New Castle with minor injuries. Unionville and Portersville volunteer fire departments assisted at the scene. Unionville Fire Chief Greg Brewster said the children, both between the ages of 7 and 11, were conscious. They were flown to the Children’s Hospital of Pittsburgh of UPMC. Brewster said the elderly man was flown to another Pittsburgh hospital. The names of those involved were not released. Brewster said the driver of the paving van failed to slow down and struck the NOGA Ambulance, causing it to flip onto its side in a ditch. The accident backed up traffic in both directions on Route 422 for more than an hour, as a section of the road was closed for the helicopters to land. It was reopened to traffic by 11 a.m.